CVE-2021-1368

Summary

CVECVE-2021-1368
StatePUBLIC
Assigner[email protected]
Source PriorityCVE Program / NVD first with legacy fallback
Published2021-02-24 20:15:00 UTC
Updated2023-11-07 03:28:00 UTC
DescriptionA vulnerability in the Unidirectional Link Detection (UDLD) feature of Cisco FXOS Software and Cisco NX-OS Software could allow an unauthenticated, adjacent attacker to execute arbitrary code with administrative privileges or cause a denial of service (DoS) condition on an affected device. This vulnerability is due to insufficient input validation. An attacker could exploit this vulnerability by sending crafted Cisco UDLD protocol packets to a directly connected, affected device. A successful exploit could allow the attacker to execute arbitrary code with administrative privileges or cause the Cisco UDLD process to crash and restart multiple times, causing the affected device to reload and resulting in a DoS condition. Note: The UDLD feature is disabled by default, and the conditions to exploit this vulnerability are strict. The attacker needs full control of a directly connected device. That device must be connected over a port channel that has UDLD enabled. To trigger arbitrary code execution, both the UDLD-enabled port channel and specific system conditions must exist. In the absence of either the UDLD-enabled port channel or the system conditions, attempts to exploit this vulnerability will result in a DoS condition. It is possible, but highly unlikely, that an attacker could control the necessary conditions for exploitation. The CVSS score reflects this possibility. However, given the complexity of exploitation, Cisco has assigned a Medium Security Impact Rating (SIR) to this vulnerability.

Risk And Classification

Problem Types: CWE-787

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
Hardware Cisco Firepower 4110 - All All All
Hardware Cisco Firepower 4110 - All All All
Hardware Cisco Firepower 4110 - All All All
Hardware Cisco Firepower 4112 - All All All
Hardware Cisco Firepower 4112 - All All All
Hardware Cisco Firepower 4112 - All All All
Hardware Cisco Firepower 4115 - All All All
Hardware Cisco Firepower 4115 - All All All
Hardware Cisco Firepower 4115 - All All All
Hardware Cisco Firepower 4120 - All All All
Hardware Cisco Firepower 4120 - All All All
Hardware Cisco Firepower 4120 - All All All
Hardware Cisco Firepower 4125 - All All All
Hardware Cisco Firepower 4125 - All All All
Hardware Cisco Firepower 4125 - All All All
Hardware Cisco Firepower 4140 - All All All
Hardware Cisco Firepower 4140 - All All All
Hardware Cisco Firepower 4140 - All All All
Hardware Cisco Firepower 4145 - All All All
Hardware Cisco Firepower 4145 - All All All
Hardware Cisco Firepower 4145 - All All All
Hardware Cisco Firepower 4150 - All All All
Hardware Cisco Firepower 4150 - All All All
Hardware Cisco Firepower 4150 - All All All
Hardware Cisco Firepower 9300 - All All All
Hardware Cisco Firepower 9300 - All All All
Hardware Cisco Firepower 9300 - All All All
Operating System Cisco Firepower Extensible Operating System r231 All All All
Operating System Cisco Fxos r231 All All All
Operating System Cisco Fxos r231 All All All
Hardware Cisco Mds 9148s - All All All
Hardware Cisco Mds 9148s - All All All
Hardware Cisco Mds 9148s - All All All
Hardware Cisco Mds 9250i - All All All
Hardware Cisco Mds 9250i - All All All
Hardware Cisco Mds 9250i - All All All
Hardware Cisco Mds 9706 - All All All
Hardware Cisco Mds 9706 - All All All
Hardware Cisco Mds 9706 - All All All
Hardware Cisco Mds 9710 - All All All
Hardware Cisco Mds 9710 - All All All
Hardware Cisco Mds 9710 - All All All
Hardware Cisco Nexus 3048 - All All All
Hardware Cisco Nexus 3048 - All All All
Hardware Cisco Nexus 3048 - All All All
Hardware Cisco Nexus 31108pv-v - All All All
Hardware Cisco Nexus 31108pv-v - All All All
Hardware Cisco Nexus 31108pv-v - All All All
Hardware Cisco Nexus 31108tc-v - All All All
Hardware Cisco Nexus 31108tc-v - All All All
Hardware Cisco Nexus 31108tc-v - All All All
Hardware Cisco Nexus 31128pq - All All All
Hardware Cisco Nexus 31128pq - All All All
Hardware Cisco Nexus 31128pq - All All All
Hardware Cisco Nexus 3132c-z - All All All
Hardware Cisco Nexus 3132c-z - All All All
Hardware Cisco Nexus 3132c-z - All All All
Hardware Cisco Nexus 3132q-v - All All All
Hardware Cisco Nexus 3132q-v - All All All
Hardware Cisco Nexus 3132q-v - All All All
Hardware Cisco Nexus 3132q-x - All All All
Hardware Cisco Nexus 3132q-x - All All All
Hardware Cisco Nexus 3132q-x - All All All
Hardware Cisco Nexus 3132q-xl - All All All
Hardware Cisco Nexus 3132q-xl - All All All
Hardware Cisco Nexus 3132q-xl - All All All
Hardware Cisco Nexus 3164q - All All All
Hardware Cisco Nexus 3164q - All All All
Hardware Cisco Nexus 3164q - All All All
Hardware Cisco Nexus 3172pq - All All All
Hardware Cisco Nexus 3172pq - All All All
Hardware Cisco Nexus 3172pq - All All All
Hardware Cisco Nexus 3172pq-xl - All All All
Hardware Cisco Nexus 3172pq-xl - All All All
Hardware Cisco Nexus 3172pq-xl - All All All
Hardware Cisco Nexus 3232c - All All All
Hardware Cisco Nexus 3232c - All All All
Hardware Cisco Nexus 3232c - All All All
Hardware Cisco Nexus 3264c-e - All All All
Hardware Cisco Nexus 3264c-e - All All All
Hardware Cisco Nexus 3264c-e - All All All
Hardware Cisco Nexus 3264q - All All All
Hardware Cisco Nexus 3264q - All All All
Hardware Cisco Nexus 3264q - All All All
Hardware Cisco Nexus 3408-s - All All All
Hardware Cisco Nexus 3408-s - All All All
Hardware Cisco Nexus 3408-s - All All All
Hardware Cisco Nexus 34180yc - All All All
Hardware Cisco Nexus 34180yc - All All All
Hardware Cisco Nexus 34180yc - All All All
Hardware Cisco Nexus 3432d-s - All All All
Hardware Cisco Nexus 3432d-s - All All All
Hardware Cisco Nexus 3432d-s - All All All
Hardware Cisco Nexus 3464c - All All All
Hardware Cisco Nexus 3464c - All All All
Hardware Cisco Nexus 3464c - All All All
Hardware Cisco Nexus 3524-x - All All All
Hardware Cisco Nexus 3524-x - All All All
Hardware Cisco Nexus 3524-x - All All All
Hardware Cisco Nexus 3524-xl - All All All
Hardware Cisco Nexus 3524-xl - All All All
Hardware Cisco Nexus 3524-xl - All All All
Hardware Cisco Nexus 3548-x - All All All
Hardware Cisco Nexus 3548-x - All All All
Hardware Cisco Nexus 3548-x - All All All
Hardware Cisco Nexus 3548-xl - All All All
Hardware Cisco Nexus 3548-xl - All All All
Hardware Cisco Nexus 3548-xl - All All All
Hardware Cisco Nexus 36180yc-r - All All All
Hardware Cisco Nexus 36180yc-r - All All All
Hardware Cisco Nexus 36180yc-r - All All All
Hardware Cisco Nexus 3636c-r - All All All
Hardware Cisco Nexus 3636c-r - All All All
Hardware Cisco Nexus 3636c-r - All All All
Hardware Cisco Nexus 5548p - All All All
Hardware Cisco Nexus 5548p - All All All
Hardware Cisco Nexus 5548p - All All All
Hardware Cisco Nexus 5548up - All All All
Hardware Cisco Nexus 5548up - All All All
Hardware Cisco Nexus 5548up - All All All
Hardware Cisco Nexus 5596t - All All All
Hardware Cisco Nexus 5596t - All All All
Hardware Cisco Nexus 5596t - All All All
Hardware Cisco Nexus 5596up - All All All
Hardware Cisco Nexus 5596up - All All All
Hardware Cisco Nexus 5596up - All All All
Hardware Cisco Nexus 56128p - All All All
Hardware Cisco Nexus 56128p - All All All
Hardware Cisco Nexus 56128p - All All All
Hardware Cisco Nexus 5624q - All All All
Hardware Cisco Nexus 5624q - All All All
Hardware Cisco Nexus 5624q - All All All
Hardware Cisco Nexus 5648q - All All All
Hardware Cisco Nexus 5648q - All All All
Hardware Cisco Nexus 5648q - All All All
Hardware Cisco Nexus 5672up - All All All
Hardware Cisco Nexus 5672up - All All All
Hardware Cisco Nexus 5672up - All All All
Hardware Cisco Nexus 5672up-16g - All All All
Hardware Cisco Nexus 5672up-16g - All All All
Hardware Cisco Nexus 5672up-16g - All All All
Hardware Cisco Nexus 5696q - All All All
Hardware Cisco Nexus 5696q - All All All
Hardware Cisco Nexus 5696q - All All All
Hardware Cisco Nexus 6001 - All All All
Hardware Cisco Nexus 6001 - All All All
Hardware Cisco Nexus 6001 - All All All
Hardware Cisco Nexus 6004 - All All All
Hardware Cisco Nexus 6004 - All All All
Hardware Cisco Nexus 6004 - All All All
Hardware Cisco Nexus 7000 - All All All
Hardware Cisco Nexus 7000 - All All All
Hardware Cisco Nexus 7000 - All All All
Hardware Cisco Nexus 7700 - All All All
Hardware Cisco Nexus 7700 - All All All
Hardware Cisco Nexus 7700 - All All All
Hardware Cisco Nexus 9000v - All All All
Hardware Cisco Nexus 9000v - All All All
Hardware Cisco Nexus 9000v - All All All
Hardware Cisco Nexus 92160yc-x - All All All
Hardware Cisco Nexus 92160yc-x - All All All
Hardware Cisco Nexus 92160yc-x - All All All
Hardware Cisco Nexus 9221c - All All All
Hardware Cisco Nexus 9221c - All All All
Hardware Cisco Nexus 9221c - All All All
Hardware Cisco Nexus 92300yc - All All All
Hardware Cisco Nexus 92300yc - All All All
Hardware Cisco Nexus 92300yc - All All All
Hardware Cisco Nexus 92304qc - All All All
Hardware Cisco Nexus 92304qc - All All All
Hardware Cisco Nexus 92304qc - All All All
Hardware Cisco Nexus 92348gc-x - All All All
Hardware Cisco Nexus 92348gc-x - All All All
Hardware Cisco Nexus 92348gc-x - All All All
Hardware Cisco Nexus 9236c - All All All
Hardware Cisco Nexus 9236c - All All All
Hardware Cisco Nexus 9236c - All All All
Hardware Cisco Nexus 9272q - All All All
Hardware Cisco Nexus 9272q - All All All
Hardware Cisco Nexus 9272q - All All All
Hardware Cisco Nexus 93108tc-ex - All All All
Hardware Cisco Nexus 93108tc-ex - All All All
Hardware Cisco Nexus 93108tc-ex - All All All
Hardware Cisco Nexus 93108tc-ex-24 - All All All
Hardware Cisco Nexus 93108tc-ex-24 - All All All
Hardware Cisco Nexus 93108tc-ex-24 - All All All
Hardware Cisco Nexus 93108tc-fx - All All All
Hardware Cisco Nexus 93108tc-fx - All All All
Hardware Cisco Nexus 93108tc-fx - All All All
Hardware Cisco Nexus 93108tc-fx-24 - All All All
Hardware Cisco Nexus 93108tc-fx-24 - All All All
Hardware Cisco Nexus 93108tc-fx-24 - All All All
Hardware Cisco Nexus 93120tx - All All All
Hardware Cisco Nexus 93120tx - All All All
Hardware Cisco Nexus 93120tx - All All All
Hardware Cisco Nexus 93128tx - All All All
Hardware Cisco Nexus 93128tx - All All All
Hardware Cisco Nexus 93128tx - All All All
Hardware Cisco Nexus 9316d-gx - All All All
Hardware Cisco Nexus 9316d-gx - All All All
Hardware Cisco Nexus 9316d-gx - All All All
Hardware Cisco Nexus 93180lc-ex - All All All
Hardware Cisco Nexus 93180lc-ex - All All All
Hardware Cisco Nexus 93180lc-ex - All All All
Hardware Cisco Nexus 93180yc-ex - All All All
Hardware Cisco Nexus 93180yc-ex - All All All
Hardware Cisco Nexus 93180yc-ex - All All All
Hardware Cisco Nexus 93180yc-ex-24 - All All All
Hardware Cisco Nexus 93180yc-ex-24 - All All All
Hardware Cisco Nexus 93180yc-ex-24 - All All All
Hardware Cisco Nexus 93180yc-fx - All All All
Hardware Cisco Nexus 93180yc-fx - All All All
Hardware Cisco Nexus 93180yc-fx - All All All
Hardware Cisco Nexus 93180yc-fx-24 - All All All
Hardware Cisco Nexus 93180yc-fx-24 - All All All
Hardware Cisco Nexus 93180yc-fx-24 - All All All
Hardware Cisco Nexus 93180yc-fx3 - All All All
Hardware Cisco Nexus 93180yc-fx3 - All All All
Hardware Cisco Nexus 93180yc-fx3 - All All All
Hardware Cisco Nexus 93180yc-fx3s - All All All
Hardware Cisco Nexus 93180yc-fx3s - All All All
Hardware Cisco Nexus 93180yc-fx3s - All All All
Hardware Cisco Nexus 93216tc-fx2 - All All All
Hardware Cisco Nexus 93216tc-fx2 - All All All
Hardware Cisco Nexus 93216tc-fx2 - All All All
Hardware Cisco Nexus 93240yc-fx2 - All All All
Hardware Cisco Nexus 93240yc-fx2 - All All All
Hardware Cisco Nexus 93240yc-fx2 - All All All
Hardware Cisco Nexus 9332pq - All All All
Hardware Cisco Nexus 9332pq - All All All
Hardware Cisco Nexus 9332pq - All All All
Hardware Cisco Nexus 93360yc-fx2 - All All All
Hardware Cisco Nexus 93360yc-fx2 - All All All
Hardware Cisco Nexus 93360yc-fx2 - All All All
Hardware Cisco Nexus 9336c-fx2 - All All All
Hardware Cisco Nexus 9336c-fx2 - All All All
Hardware Cisco Nexus 9336c-fx2 - All All All
Hardware Cisco Nexus 9336c-fx2-e - All All All
Hardware Cisco Nexus 9336c-fx2-e - All All All
Hardware Cisco Nexus 9336c-fx2-e - All All All
Hardware Cisco Nexus 9336pq - All All All
Hardware Cisco Nexus 9336pq - All All All
Hardware Cisco Nexus 9336pq - All All All
Hardware Cisco Nexus 9348gc-fxp - All All All
Hardware Cisco Nexus 9348gc-fxp - All All All
Hardware Cisco Nexus 9348gc-fxp - All All All
Hardware Cisco Nexus 93600cd-gx - All All All
Hardware Cisco Nexus 93600cd-gx - All All All
Hardware Cisco Nexus 93600cd-gx - All All All
Hardware Cisco Nexus 9364c - All All All
Hardware Cisco Nexus 9364c - All All All
Hardware Cisco Nexus 9364c - All All All
Hardware Cisco Nexus 9364c-gx - All All All
Hardware Cisco Nexus 9364c-gx - All All All
Hardware Cisco Nexus 9364c-gx - All All All
Hardware Cisco Nexus 9372px - All All All
Hardware Cisco Nexus 9372px - All All All
Hardware Cisco Nexus 9372px - All All All
Hardware Cisco Nexus 9372px-e - All All All
Hardware Cisco Nexus 9372px-e - All All All
Hardware Cisco Nexus 9372px-e - All All All
Hardware Cisco Nexus 9372tx - All All All
Hardware Cisco Nexus 9372tx - All All All
Hardware Cisco Nexus 9372tx - All All All
Hardware Cisco Nexus 9372tx-e - All All All
Hardware Cisco Nexus 9372tx-e - All All All
Hardware Cisco Nexus 9372tx-e - All All All
Hardware Cisco Nexus 9396px - All All All
Hardware Cisco Nexus 9396px - All All All
Hardware Cisco Nexus 9396px - All All All
Hardware Cisco Nexus 9396tx - All All All
Hardware Cisco Nexus 9396tx - All All All
Hardware Cisco Nexus 9396tx - All All All
Hardware Cisco Nexus 9508 - All All All
Hardware Cisco Nexus 9508 - All All All
Hardware Cisco Nexus 9508 - All All All
Operating System Cisco Nx-os 7.0\(3\)i5\(2\) All All All
Operating System Cisco Nx-os 7.0\(3\)i7\(9\) All All All
Operating System Cisco Nx-os 7.3\(8\)n1\(1\) All All All
Operating System Cisco Nx-os 7.3\(9\)n1\(0.823\) All All All
Operating System Cisco Nx-os 8.4\(3.108\) All All All
Operating System Cisco Nx-os 8.4\(3.117\) All All All
Operating System Cisco Nx-os 9.3\(5\) All All All
Operating System Cisco Nx-os 7.0\(3\)i5\(2\) All All All
Operating System Cisco Nx-os 7.0\(3\)i7\(9\) All All All
Operating System Cisco Nx-os 7.3\(8\)n1\(1\) All All All
Operating System Cisco Nx-os 7.3\(9\)n1\(0.823\) All All All
Operating System Cisco Nx-os 8.4\(3.108\) All All All
Operating System Cisco Nx-os 8.4\(3.117\) All All All
Operating System Cisco Nx-os 9.3\(5\) All All All
Hardware Cisco Ucs 6248up - All All All
Hardware Cisco Ucs 6248up - All All All
Hardware Cisco Ucs 6248up - All All All
Hardware Cisco Ucs 6296up - All All All
Hardware Cisco Ucs 6296up - All All All
Hardware Cisco Ucs 6296up - All All All
Hardware Cisco Ucs 6324 - All All All
Hardware Cisco Ucs 6324 - All All All
Hardware Cisco Ucs 6324 - All All All
Hardware Cisco Ucs 6332 - All All All
Hardware Cisco Ucs 6332 - All All All
Hardware Cisco Ucs 6332 - All All All
Hardware Cisco Ucs 6332-16up - All All All
Hardware Cisco Ucs 6332-16up - All All All
Hardware Cisco Ucs 6332-16up - All All All
Hardware Cisco Ucs 64108 - All All All
Hardware Cisco Ucs 64108 - All All All
Hardware Cisco Ucs 64108 - All All All
Hardware Cisco Ucs 6454 - All All All
Hardware Cisco Ucs 6454 - All All All
Hardware Cisco Ucs 6454 - All All All
Application Cisco Unified Computing System All All All All
Application Cisco Unified Computing System All All All All

References

ReferenceSourceLinkTags
Cisco FXOS and NX-OS Software Unidirectional Link Detection Denial of Service and Arbitrary Code Execution Vulnerability CISCO tools.cisco.com Vendor Advisory
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis
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